Method and apparatus for the production of an ornamental shoe sole welt, border, or the like, on shoe soles of rubber or the like



March 27, 1951 o MAJTNER 2,546,553

METHOD AND APPARATUS FOR THE PRODUCTION OF AN ORNAMENTAL SHOE SOLE WELT, BORDER OR THE LIKE-ON SHOE SOLES OF RUBBER OR THE LIKE Fild July 1, 1948 Gttomcgs.

Patented Mar. 27, 1951 METHOD AND APPARATUS FOR THE PRO- ORNAMENTAL SHOE SGLE VVEL'I, BORDER, OR THE LIKE, ON SHQE SOLES OF RUBBER OR THE LIKE ()ldi'ich Majtner, Zlin, Czechoslovakia, assignor to Svit, narodni podnik, Gottwaldov, Czecho- DUGTIGN OF AN slovakia Application July 1, 1948, Serial No. 36,544 In Czechoslovakia July 21, 1%?

(Cl. 12 m 8 Claims.

The present invention relates broadly to the manufacture of shoes and more particularly to a method for producing a shoe sole welt, border or the like and to an apparatus for carrying out the new method.

An object of the present invention is to permit the manufacture of rubber ornamental welts with an imitation of sewing stitches on the same.

An imitation of sewn through stitches, e. g. on rubber soles, has been obtained hitherto in various ways, which however are all too complicated and moreover do not permit to obtain a perfect imitation of a Welt with sewn through stitches.

Thus, for instance, the United States Patent No. 2,093,523 describes a method of imitating sewing stitches in which a. rubber welt having the same colour as the leather and secured to a shoe sole by means of a suitable cement, is provided on its surface with a groove in which strips of a rubber compound having the same colour as that of the leather are laid, the said strips having on their surface a narrow band of a white rubber compound interrupted at uniformiy spaced intervals.

Another method in accordance with the same invention consists in assembling the welt of two strips of the same colour as that of the leather, and of an intermediate third strip of the same colour as the sewing yarn, this last mentioned strip being located between the first two strips and interrupted at regular intervals.

A still further method in accordance with the invention referred to consists in the insertion into a groove provided in a rubber welt, of a strip having the same colour as the sewing yarn and formed on its surface with uniformly spaced projections corresponding to apertures formed in another rubber strip which has the same colour as that of the leather and is laid over the surface of the composite welt in such a manner that the said projections extend through the apertures in the second strip beyond the level of the welt.

The above described methods are very unpractical and make diiiicult the entire process of producing ornamental welts. Due to their complicated nature, the said methods require a relatively great precision both in the preparation of the separate parts and in assembling the same to form the ornamental welt. It is not an easy matter to obtain the required accuracy since the manufacturing process is a complicated one and the rubber parts under treatment are in a plastic state. As a consequence, the product itself ob- 2 tained by the methods of manufacture referred to is not satisfactory in so far as the accuracy of the imitation of sewn through stitches on an ornamental sole welt is concerned.

Therefore, a perfect imitation of sewn through stitches and at the same time an easy manufacture of ornamental welts may be secured mainly by simplifying the manufacturing process. The method in accordance with the present invention permits to secure full success in this respect.

The essential features of the invention consists in placing on a rubber welt, which is still in a plastic condition, a rubber strand also in plastic condition and having the same colour, shape and thickness as the yarn to be imitated, the said strand being caused to adhere to the welt by means, for instance, of a profiled roller with concurrent shaping of the imitation of stitches, and then vulcanising the strand together with the welt which is supported e. g. on a rubber sole. This method of making an ornamental welt in accordance with the present invention permits continuous production, using for this purpose preferably an extrusion press. Depending on the composition of the welt, two extrusion nozzles are usually used, one for the Welt and the other for the yarn imitating rubber strand. Alternatively it may be of advantage to use an extrusion machine provided with a single nozzle for extruding a, two coloured mixture.

An example of carrying out the method in accordance with the invention will be described more in detail with reference to the accompanying drawings, in which 1 shows diagrammatically the working process for making an ornamental welt in accordance with the present invention;

Fig. 2 is a detail View on a larger scale of the imitation of sewn through stitches on a welt; and

Fig. 3 is a detail View similar to Fig. 2, illustrating ornamental indentations as well as the imitation of sewn through stitches on a welt.

Referring to the drawings, two rubber compounds having each the desired color, e. g. one of them the colour of the leather and the other that of the sewing thread, are extruded concurrently at the same speed through two nozzles I, 2 of an extrusion machine, the nozzles having a suitable shape to give the desired profile to the extruded material. Both the base welt A and the rubber strand 3, which is intended to imitate the sewing yarn, pass between centering rollers 5, 6 and pressure rollers l, 8, whereby the strand 3 is laid on the base welt and caused to adhere to the latter at a uniform spacing from the edge of the same. From the pressure rollers 'l and 8 the welt passes over a roller 9, which serves as a support for the part ii] of the rubber welt, and is directed under a toothed compression roller l l. The compression roller l I operates to guide the welt, with the sewing yarn imitating strand adhering to the latter, and to cause the Welt to be adhesively fastened by pressure to the edge of a sole l2, and on the other hand, by means of its teeth travelling over the face of the welt, the said roller ll forms at the same time indentations i l in the rubber strand to form imitation stitches 13, as shown in Fig. 2. In order to enhance the appearance further, the teeth of the compression roller may also be shaped to form indentations M in the surface of the welt as shown in Fig. 3, the said indentations being of assistance in giving an impression as it the welt were actually sewn through by means of stitches l3.

This method of imitating sewing stitches may be used with advantage also in connection with other ornamental or like work, e. g. to imitate ornamental sewing stitches on rubber borders of footwear, ornamental ribbons, hems and the like.

The process of manufacturing a welt with sewing stitch imitation, more particularly the process of laying a strip of rubber at the desired location on a base welt and/or conveying the welt to the toothed compression roller, is not limited to the constructional details as described and diagrammatically illustrated, since the construction shown does not exhaust all the possible embodiments of the method for the continuous production of ornamental welts with sewing stitch imitation in accordance with the present invention.

What I claim is:

1. In a method for the production of an ornamental shoe sole with a welt, border or the like with imitation of sewing stitches, the steps of placing in the desired position on a, rubber welt, which is still in plastic condition, a rubber strand, also in plastic condition, and having the same colour, shape and thickness as the yarn to be imitated, causing the said rubber strand to adhere to the welt, laying the welt together with the yarn imitating strand on a shoe sole, pressing the welt against the shoe sole and concurrently shaping the rubber strand to imitate sewing stitches.

2. In a method for the production of an ornamental shoe sole welt, border or the like, the steps of continuously extruding a base rubber welt and a rubber strand having the same colour, shape and thickness as the yarn to be imitated, straightening the rubber welt and the yarn imitating rubber strand, pressing together the rubber welt and the yarn imitating rubber strand, laying the welt together with the yarn imitating strand on a shoe sole, pressing the welt against the shoe sole and concurrently shaping the rubber strand to imitate sewing stitches.

3. In a method for the production of an ornamental shoe sole welt, border or the like, the steps of continuously extruding a base rubber welt and a rubber strand having the same colour, shape and thickness as the yarn to be imitated, straightening the rubber welt and the yarn imitating rubber strand, pressing together the rubber welt and the yarn imitating rubber strand, laying the welt together with the yarn imitating strand on a shoe sole, pressing the welt against the shoe sole and concurrently shaping the rubber strand to imitate sewing stitches and forming ornamental indentations in the rubber welt.

4. In a method for the production of an ornamental shoe sole welt, border or the like, the steps of continuously extruding a base rubber welt and a rubber strand having the same colour, shape and thickness as the yarn to be imitated, uniting the rubber welt and the rubber strand in the extrusion nozzle itself, straightening the rubber and the yarn imitating rubber strand, pressing together the rubber welt and the yarn imitating rubber strand, laying the welt together with the yarn imitating strand on a shoe sole, pressing the welt against the shoe sole and concurrently shaping the rubber strand to imitate sewing stitches and forming ornamental indentations in the rubber welt.

5. In an apparatus for the production of an ornamental shoe sole welt, border or the like, the provision of means for continuously extruding a base rubber welt and a yarn imitating rubber strand, means for straightening the welt and the stand, means for pressing together the rubber welt and the yarn imitating rubber strand, means for laying the welt and yarn imitating strand on a shoe sole, and mean for pressing the welt against the shoe sole to cause it to adhere to the shoe sole and for concurrently shaping the strand to imitate sewing stitches.

6. The apparatus as set forth in claim 5, in which two extrusion nozzles are provided, one for the rubber welt and the other for the yarn imitating rubber strand.

7. In an apparatus for the production of an ornamental shoe sole welt, border or the like, means for continuously extruding a base rubber welt and a rubber strand having the same colour, shape and thickness as the yarn to be imitated, a pair of rollers for straightening the rubber welt and the yarn imitating rubber strand, a second pair of rollers for pressing together the rubber welt and the rubber strand, a guide roller for supporting the rubber welt and rubber strand and a toothed roller for laying the welt together with the yarn imitating strand on a shoe sole, pressing the welt against the shoe sole and shaping the rubber strand to imitate sewing stitches.

8. An apparatus set forth in claim 7, in which the toothed roller is also adapted to form ornamental indentations in the rubber welt.

OLDRICH MAJTNER.

No references cited. 

